/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.iotdb;

import org.apache.iotdb.session.Session;
import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
import org.apache.iotdb.tsfile.utils.Binary;
import org.apache.iotdb.tsfile.write.record.Tablet;
import org.apache.iotdb.tsfile.write.schema.MeasurementSchema;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

public class TabletExample {

    private static final String TIME_STR = "time";

    /**
     * load csv data.
     *
     * @param measureTSTypeInfos key: measurement name, value: measurement data type
     * @param dataFileName       the csv file name to load
     * @return key: measurement name, value: series in format of {@link ArrayList}
     * @throws IOException if the csv format is incorrect
     */
    private static Map<String, ArrayList> loadCSVData(
            Map<String, TSDataType> measureTSTypeInfos, String dataFileName) throws IOException {
        measureTSTypeInfos.put(TIME_STR, TSDataType.INT64);
        try (BufferedReader reader = new BufferedReader(new FileReader(dataFileName))) {
            String headline = reader.readLine();
            if (headline == null) {
                throw new IOException("Given csv data file has not headers");
            }
            // check the csv file format
            String[] fileColumns = headline.split(",");
            Map<String, Integer> columnToIdMap = new HashMap<>();
            for (int col = 0; col < fileColumns.length; col++) {
                String columnName = fileColumns[col];
                if (columnToIdMap.containsKey(columnName)) {
                    throw new IOException(
                            String.format("csv file contains duplicate columns: %s", columnName));
                }
                columnToIdMap.put(columnName, col);
            }
            Map<String, ArrayList> ret = new HashMap<>();
            // make sure that all measurements can be found from the data file
            for (Entry<String, TSDataType> entry : measureTSTypeInfos.entrySet()) {
                String measurement = entry.getKey();
                if (!columnToIdMap.containsKey(entry.getKey())) {
                    throw new IOException(String.format("measurement %s's is not in csv file.", measurement));
                } else {
                    ret.put(measurement, new ArrayList<>());
                }
            }

            String line;
            while ((line = reader.readLine()) != null) {
                String[] items = line.split(",");
                for (Entry<String, TSDataType> entry : measureTSTypeInfos.entrySet()) {
                    String measurement = entry.getKey();
                    TSDataType dataType = entry.getValue();
                    int idx = columnToIdMap.get(measurement);
                    switch (dataType) {
                        case BOOLEAN:
                            ret.get(measurement).add(Boolean.parseBoolean(items[idx]));
                            break;
                        case INT32:
                            ret.get(measurement).add(Integer.parseInt(items[idx]));
                            break;
                        case INT64:
                            ret.get(measurement).add(Long.parseLong(items[idx]));
                            break;
                        case FLOAT:
                            ret.get(measurement).add(Float.parseFloat(items[idx]));
                            break;
                        case DOUBLE:
                            ret.get(measurement).add(Double.parseDouble(items[idx]));
                            break;
                        case TEXT:
                            ret.get(measurement).add(Binary.valueOf(items[idx]));
                            break;
                        case VECTOR:
                            throw new IOException(String.format("data type %s is not yet.", TSDataType.VECTOR));
                    }
                }
            }
            return ret;
        } finally {
            measureTSTypeInfos.remove(TIME_STR);
        }
    }

    /**
     * Read csv file and insert tablet to IoTDB
     *
     * @param args: arg(with default value): arg0: dataFileName(sample.csv), arg1: rowSize(10000),
     *              arg2: colSize(5000).
     */
    public static void main(String[] args) throws Exception {

        Session session = new Session("127.0.0.1", 6667, "root", "root");
        session.open();
        String dataFileName = "sample.csv";
        int rowSize = 10000;
        int colSize = 5000;
        if (args.length > 1) {
            dataFileName = args[0];
        }
        if (args.length > 2) {
            rowSize = Integer.parseInt(args[1]);
        }
        if (args.length > 3) {
            colSize = Integer.parseInt(args[2]);
        }

        // construct the tablet's measurements.
        Map<String, TSDataType> measureTSTypeInfos = new HashMap<>();
        measureTSTypeInfos.put("s0", TSDataType.BOOLEAN);
        measureTSTypeInfos.put("s1", TSDataType.FLOAT);
        measureTSTypeInfos.put("s2", TSDataType.INT32);
        measureTSTypeInfos.put("s3", TSDataType.DOUBLE);
        measureTSTypeInfos.put("s4", TSDataType.INT64);
        measureTSTypeInfos.put("s5", TSDataType.TEXT);
        List<MeasurementSchema> schemas = new ArrayList<>();
        measureTSTypeInfos.forEach((mea, type) -> schemas.add(new MeasurementSchema(mea, type)));

        System.out.println(
                String.format(
                        "Test Java: csv file name: %s, row: %d, col: %d", dataFileName, rowSize, colSize));
        System.out.println(String.format("Total points: %d", rowSize * colSize * schemas.size()));

        // test start
        long allStart = System.nanoTime();

        Map<String, ArrayList> data = loadCSVData(measureTSTypeInfos, dataFileName);
        long loadCost = System.nanoTime() - allStart;

        long insertCost = 0;
        for (int i = 0; i < colSize; i++) {
            String deviceId = "root.sg" + i % 8 + "." + i;

            Tablet ta = new Tablet(deviceId, schemas, rowSize);
            ta.rowSize = rowSize;
            for (int t = 0; t < ta.rowSize; t++) {
                ta.addTimestamp(t, (Long) data.get(TIME_STR).get(t));
                for (Entry<String, TSDataType> entry : measureTSTypeInfos.entrySet()) {
                    String mea = entry.getKey();
                    ta.addValue(mea, t, data.get(mea).get(t));
                }
            }
            long insertSt = System.nanoTime();
            session.insertTablet(ta, false);
            insertCost += (System.nanoTime() - insertSt);
        }
        // test end
        long allEnd = System.nanoTime();

        session.executeNonQueryStatement("delete timeseries root.*");
        session.close();

        System.out.println(String.format("load cost: %.3f", ((float) loadCost / 1000_000_000)));
        System.out.println(
                String.format(
                        "construct tablet cost: %.3f",
                        ((float) (allEnd - allStart - insertCost - loadCost) / 1000_000_000)));
        System.out.println(
                String.format("insert tablet cost: %.3f", ((float) insertCost / 1000_000_000)));
        System.out.println(
                String.format("total cost: %.3f", ((float) (allEnd - allStart) / 1000_000_000)));
        System.out.println(String.format("%.3f", ((float) loadCost / 1000_000_000)));
    }
}
